This invention relates generally to development apparatus for mixing and applying developer material to a latent image on an image-bearing member in an electrographic reproduction machine, such as a copier or printer. More particularly, this invention relates to a blender of the type for mixing electrographic developer comprising a plurality of blender segments mounted on a shaft.
Development apparatus, for example a magnetic brush development apparatus, are well known for mixing and applying developer material to a latent electrostatic image on a photoconductor in an electrostatographic reproduction machine such as a copier or printer. Such a development apparatus typically includes an elongate housing which has a sump portion for containing the developer material. A two-component developer material comprises a mixture of carrier particles and toner particles. These particles are usually moved and mixed by a mixing device in the sump portion of the housing for triboelectrically charging the particles. Mixing also promotes uniformity in the concentration of toner particles throughout the sump portion, and in the distribution of developer material within the sump. The mixed and charged developer material can then be fed from the sump portion for development of the latent image on the photoconductor, which is generally a film or drum.
The quality of such an image development depends, in significant part, on factors such as the level of charge on the toner particles achieved triboelectrically for example, and such as the level and uniformity of the concentration of toner particles in the developer material being applied. As is well known, these factors are mainly determined by the effectiveness of a mixing device used in the sump portion of the development apparatus housing for moving, mixing and charging the developer material particles.